Improvement in steam-boilers



R. DEMPSTER.

STEAM-BOIVLER. No."170,34;8 Patented Nov. 23, 187'5.

UNITED STATES PATENT OFFICE.

ROBERT DEMPSTER, OF BUFFALO, NEW YORK, ASSIGNOB. OF ONE-HALF HS'BIGHT TO JOHN M. OOMSTOOK, OF SAME PLACE.

IMPROVEMENT IN STEAM-BOILERS.

Specification forming part of Letters Patent No. 170,348, dated November 23, 1875; application filed October 8, 1875.

To all whom it may concern:

Be it known that l, ROBERT DEMPsTEE, of. the city of Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Steam-Boilers, which improvements are fully set forth in the following specification, reference being had to the accompanying drawings.

The object of this invention is to provide a simple, convenient, and durable portable steam-boiler; and it consists of a removable annular steam-chamber, formingthe top ofthe boiler, and the opening through which the fuel is introduced; an annular waterspace compartment, which forms the outer and inner shell of the sides of the boiler; and inside annular Water-space compartment, placed on a level, or nearly so, with the grate-surface, and arranged so that it forms the lower part of the fuel and combustion chamber, the whole being arranged and combined with the necessary circulating and connecting tubes, as will be more clearly hereinafter shown by reference to the said drawings7 in which- Figure l is a side elevation of the boiler complete, and Fig. 2 a vertical section through the center of the same.

A represents the removable annular steamchamber, forming the top of the boiler. B, in

Fig. 1, is the cover 5 and C, in Fig. 2, the Opeliing through which the fuel is introduced. D D are tubular connections for holding the chamber A to the boiler, and for affording communication between them, all of said parts being screwed or otherwise put together, so as to be easily connected or disconnected,

.leading thereto. chamber. M is a partition separating the ashpit and all that portion below the grate from the flues N N. The direction of the currents of the products of combustion is plainly shown by the arrows. The heat and gases as they rise and heat the upper part of the combustion-chamber are drawn down by the force of the draft between the annular water-spaces and out-into the smoke-stack. P represents the door leading to the ash-pit, and Q a lever for shaking the grate.

I claim as my invention- Y The removable steam-chamber A, provlded with the opening O, tubes or pipes D D', in combination with the annular water-chamber E, forming the body of the boiler, connectingvpipes Gr G, annular water-chamber, and ref box F, pipes or connections J J', and partition M, all arranged substantially as and, for the purposes described.

ROBERT DEMPSTER.

Witnesses: l JAMEs SANGSTER, WM. S. GRosvENoE. 

